This invention relates to a fibrous material for capturing a chemical substance used in the field of separation analysis of chemical substances, such as liquid chromatography and gas chromatography, to a method for producing the material, and to a tube for capturing a chemical substance using the material.
As a material used for capturing liquid-diluted samples, a material put into a hollow polyethylene tube or a syringe-type plastic container is known. The material has silica gel particles, silica gel or polymer particles with chemically modified surfaces, assemblies of a material made of glass fibers or tetrafluoroethylene fibers tangling with silica gel particles, or the like, being held between frits in the container. It is broadly used for solid phase extraction.
A plastic container in which the assemblies of the above material are packed has a defect that flow resistance is strong. There is another defect that a great deal of solvent is required to move constituents of a sample. Furthermore, the material is liable to be unevenly bedded at the time of loading the material into the plastic container. Therefore, the capturing efficiency may decrease because large passages are generated in the loading material.
As prior art, there is also a material of a disc type in which a loading material for capturing a chemical substance is made of the above particles and formed into woven fabric, which is held between frits in the container. The material is unified and formed into a disc to be treated. The material of such a disc type needs to be sufficiently hardened in a manner of hardening the particles from the edge.
Hence, objects of the present invention are to remedy the above defects and provide a reliable material which can capture an objective chemical substance from a diluted sample and a method for producing the same, and to provide a capturing tube made of the material.
In the present invention, a material for capturing a chemical substance is made of a form of fiber, i.e., fibers which have particles made from metal alkoxide on surfaces thereof. The metal alkoxide includes oligosilica, oligozirconia, oligotitania and the like, which produce particles. In this specification, the particles mentioned above are called metal alkoxide particles.
In the present invention, a method for producing the above material includes a step of treating surfaces of the fibers to facilitate the fixation of metal alkoxide thereto, a step of forming metal alkoxide particles on the surfaces of the fibers, and a step of fixing the metal alkoxide particles to the surfaces of the fibers.
In the present invention, a tube for capturing a chemical substance is a hollow tube which holds the fibrous material for capturing a chemical substance mentioned above and captures a small amount of chemical substance from a liquid or gas.